1. From the Division of Cardiology, Department of Medicine, University of California, San Diego (L.B.D., M.S.T., H.H.W., V.T., A.M.K.); Department of Pediatrics, University of California, San Diego, La Jolla, and Rady Children's Hospital San Diego, San Diego, CA (S.J.-F., J.C.B.); Naval Medical Center San Diego (D.B.F., H.-A.L.P., P.E.L., K.N.); and Sharp Memorial Hospital and San Diego Cardiac Center, San Diego, CA (J.B.G.).